Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
No Match

r"
"
gm

Test String

Code Generator

Generated Code

#include <StringConstants.au3> ; to declare the Constants of StringRegExp #include <Array.au3> ; UDF needed for _ArrayDisplay and _ArrayConcatenate Local $sRegex = "(?m)(?:^|\b(?<!\.))(?:1?\d?\d|2[0-4]\d|25[0-5])(?:\.(?:1?\d?\d|2[0-4]\d|25[0-5])){3}(?=$|[^\w.])|(?:^|\b(?<!\.))(?:1?\d?\d|2[0-4]\d|25[0-5])(?:\.(?:1?\d?\d|2[0-4]\d|25[0-5]))(?:\.\W.*)(?:1?\d?\d|2[0-4]\d|25[0-5])|(?:1?\d?\d|2[0-4]\d|25[0-5])(?:\.(?:1?\d?\d|2[0-4]\d|25[0-5])){2}(?:\.[\W].+)(?:\})" Local $sString = "My input string & constraints are as follows :" & @CRLF & _ "" & @CRLF & _ " IPv4 Range : 0.0.0.0 to 255.255.255.255 55.123.99.988 256.1.1.1" & @CRLF & _ " IPv4 address may / may not be present in the string" & @CRLF & _ " Valid Examples : this is an ip & this is an ip 200.100.2.32" & @CRLF & _ " String may start with IPv4 address 10.250.{{ number*2 }}.5 sdsd" & @CRLF & _ " Valid Examples : 10.250.5.{{ number*2 }} asdf" & @CRLF & _ "200.100.2.{{ number*2 }} is an ip | Output : ['200.100.2.32']" & @CRLF & _ " Invalid Examples :" & @CRLF & _ "200.100.2.32is an ip | Output : []" & @CRLF & _ " String may end with IPv4 address" & @CRLF & _ " Valid Examples : the ip is 200.100.2.32" & @CRLF & _ "Output : ['200.100.2.32']" & @CRLF & _ " Invalid Examples : the ip is200.100.2.32" & @CRLF & _ "Output : []" & @CRLF & _ " String may contain an IPv4 address in the middle, and if it does - there will a space before and after the IPv4 address." & @CRLF & _ " Valid Examples : the ip is 200.100.2.32 and it is ipv4 | Output : ['200.100.2.32']" & @CRLF & _ " Valid Examples : the ip is 200.100.2.32and it is ipv4 | Output : []" & @CRLF & _ " Multiple IPs may be present in a single string" & @CRLF & _ " Valid Examples : 200.100.2.32 100.50.1.16 | Output : ['200.100.2.32', '100.50.1.16']" & @CRLF & _ " Invalid Examples : 200.100.2.32.100.50.1.16 | Output : []" & @CRLF & _ "" Local $aArray = StringRegExp($sString, $sRegex, $STR_REGEXPARRAYGLOBALFULLMATCH) Local $aFullArray[0] For $i = 0 To UBound($aArray) -1 _ArrayConcatenate($aFullArray, $aArray[$i]) Next $aArray = $aFullArray ; Present the entire match result _ArrayDisplay($aArray, "Result")

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for AutoIt, please visit: https://www.autoitscript.com/autoit3/docs/functions/StringRegExp.htm